The demand for high-speed data access is growing rapidly. In the late 90's 28 Kbps was considered fast for wired service. Now even 56 Kpbs is considered slow for wired service with 384 Kpbs considered the norm. With these higher speeds, downloading complex web pages and “rich media” such as streaming video are now practical.
Wireless operators are struggling to offer their customer a wireline type experience on wireless. Today, cellular operators offer their subscribes only limited data and no “rich media” services because they have a limited amount of licensed radio bandwidth. Typical data rates on wireless today are 9.6 Kbps. GPRS will soon raise that to 50 to 80 Kbps (115 Kbps theoretical), but even this is slow compared to wireline's 384 Kbps.
To address this issue, carriers are aggressively trying to obtain additional licensed spectrum and are aggressively pushing the engineering community to find more efficient ways of using the current and anticipated radio allocations. But the results of these actions are several years off and will cost substantial amounts of money.
Unlicensed radio is becoming very popular and very affordable of obtaining high speed wireless access. Unlicensed radio operates in the ISM (Industrial, Scientific and Medical) Bands and is limited to very low power, which means the frequencies can be reused many times over.
IEEE 802.11b is one example of unlicensed technology that is very affordable and very capable, offering speeds of up to 10,000 Kbps. An 802.11b Wireless Local Area Network (LAN) covering a small home or office and supporting 3 computers can be purchased for about $500.00 and the equipment is becoming a standard feature of many computer product lines including Dell and Apple. 802.11b is but one of several Wireless LAN technologies. Others include HomeRF, 802.11x, Bluetooth, etc.
While these technologies were originally developed for Wireless Local Area Networks (WLAN) for office and homes, a new class of service operators are emerging using this technology.
For a fee, these operators are offering public access via 802.11b networks. These networks are being installed at airports, coffee shops, etc and other places where people will use computers for an extended period of time. The present embodiments relate to the question of interfacing between the wireless LANs and the cellular or PLMN networks.
High speed unlicensed and licensed wireless access technologies are now available that will support speeds of 700 Kbps to 10 Mbps and even higher. Examples of these wireless access technologies include Bluetooth and Wireless LANs such as 802.11(x). These networks have sufficiently high speed to support rich media services such as videophones, streaming videos, etc.
PLMN subscribes can use these non-PLMN Access Networks (AN) for high-speed access to rich media services.
In some venues the non-PLMN Access network may be carrying a substantial amount of rich media that is local to the venue. An example would be a sports arena where the predominate rich media source would be near real time playback of game highlights. While this rich media could be delivered via communication through the PLMN, keeping this rich media traffic out of the core network will reduce the burden on that network.
In order to take advantage of such data but additionally be part of the larger, PLMN network, it is necessary to support, in an integrated manner, Peer-to-Peer, Peer to Local Sever and Peer to Off Network connection types in such a way that a single connecting client can take advantage of all of the connection types. This is because subscribes do not want to have multiple terminals, so supporting voice communication is also a key technical requirement.
One of the issues involved in providing such interfacing is in that PLMN type networks are designed to ensure that the only users of the network are devices that can prove that they are authorized holders of unique telephone numbers. The purpose of such design is to ensure that billing can be carried out reliably and correctly, that impersonation of other uses is not possible and that unauthorized access to the network is not in general possible. To this end the cellular telephony devices are either provided with a subscriber identity module (SIM) which is a security chip having secure keys and algorithms to identify the device to the PLMN and which in addition carries out data encryption and decryption, depending on the configuration of the specific network; or they have stored identity data that the system uses in order to authenticate them to the network.
SIMs are physical devices that are secure from duplication and internal inspection, meaning that the data can not be externally read and can not be recovered by dissecting the part.
The SIM is typically in the physical possession of the subscriber and is installed by the subscriber in the device, typically the cellular telephone, that is used for access to the network. This means the access device has a SIM card carrier and reader. The SIM concept is widely used and furthermore allows the subscriber to exchange the device being used to access the network whilst keeping the same identity and telephone number, by simply removing his SIM from the existing device and placing it in the new device
SIM based authentication is appropriate for cellular devices connecting directly to the PLMN. However it is also contemplated that users connect to a local non-PLMN network such as a Bluetooth network and from there connect via the cellular network. Furthermore the local non-PLMN network is generally compatible with a wide range of devices, such as portable computers, PDA type devices and the like which are not conventional cellular devices and which are not typically equipped with a cellular identity, SIM or even a SIM card carrier and reader. These devices are collectively designated “non-SIM devices”. It is desirable to provide an infrastructure for allowing such non-SIM devices to connect via the local network to the cellular network, or at least to approve their access to other networks e.g. Internet based on their cellular identity.
Furthermore local non-PLMN networks are by their nature very localized. A user may wish to move whilst using one and may easily find himself out of range of any convenient access point. More particularly, mobile users within a small or confined area may get service from a local Access Point (AP) using any technology suitable for short ranges in the order of 10 to 100 meters. Each such AP supports a network of local mobile users. The communication conditions between each user and the AP may vary within a large range as a result of variable propagation path loss, available transmission power, interference level and network loading.
If more than one AP is operational within the area, whether multiple APs are collocated within a single point or they are installed in proximity in separate locations, it may be that the user would be serviced with better communication conditions from a different AP than the one currently being used or considered.
The problem then is to determine whether such an alternative AP is available and get the user to connect to that alternate AP. Such a problem is solved by a range of available procedures known collectively as “handoff”.
A different problem occurs when a user is equipped with a dual technology terminal, e.g. cellular and Wireless LAN, cellular and wireline Internet access, etc, and the connection needs to be exchanged from an access point using one technology to an access point using another technology. In this case, the logic usually associated with handoff does not apply; rather, a different approach is required in order to make optimal use of the available communication resources.
Multiple technologies have been proposed to provide network connectivity within a small, confined area. Best known within this group are the 802.11 Frequency Hopping and Direct Sequence Wireless LAN (WLAN) standards and Bluetooth. The standards for these technologies treat the network as stand alone. When a member or potential member of such a network cannot obtain satisfactory data rate from the network Access Point, be it because of deteriorating communication conditions or network loading, one of several negative outcomes may occur from the user standpoint: he may be put on hold, deactivated/dropped from the network or supplied with an unacceptably low data rate. Existing solutions do not support searching for or transferring the user to another network operating in the area, i.e. there is no equivalent to the cellular handoff in which the mobile user is transferred to another Access Point that can satisfy its communication needs.
Furthermore, no standards have been proposed to control the transfer between technologies providing services to these confined areas and technologies associated with wide areas, primarily cellular; or between technologies covering wide areas through wireless and wired connectivity.
It is also necessary to consider authentication for remote connections, for example for authenticating remote transactions or for ensuring that the correct user is billed for remotely provided services, and interfacing is not complete between networks unless one network can be used to provide authentication to users connecting over channels, typically of other networks, which are not secure or over which a user cannot be positively identified.
Currently there are numerous circumstances in which transactions are carried out without the physical proximity of the transacting parties. Such circumstances include ATM transactions, credit card and other transactions made by telephone, and transactions made over the Internet. Generally, the identity of the purchasing party is not established to a high degree in such transactions. The transactions are carried out over unsecured and/or non-authenticatable connections and using communication techniques that are insecure and/or non-authenticatable, allowing users to be impersonated and credit card numbers to be stolen.
Currently, arrangements for electronic payment rely very heavily on credit cards, which make it difficult to levy small charges, such as time charges for use of a network, or small charges for downloading of data items.
Currently there are numerous circumstances in which transactions are carried out without the physical proximity of the transacting parties. Such circumstances include ATM transactions, credit card and other transactions made by telephone, and transactions made over the Internet. Generally, the identity of the purchasing party is not established to a high degree in such transactions. The transactions are carried out over unsecured and/or non-authenticatable connections and using communication techniques that are insecure and/or non-authenticatable, allowing users to be impersonated and credit card numbers to be stolen.
Currently, arrangements for electronic payment rely very heavily on credit cards, which make it difficult to levy small charges, such as time charges for use of a network, or small charges for downloading of data items: